Introduction to the Skeletal System
Your skeletal system has two major divisions. The axial skeleton includes your skull (8 cranial and 14 facial bones), vertebral column (7 cervical, 12 thoracic, 5 lumbar vertebrae, plus the sacrum and coccyx), 12 pairs of ribs, sternum, hyoid bone, and ear ossicles. The appendicular skeleton contains all your limbs and their connections—shoulders, arms, hips, legs, hands, and feet.
The skeletal system serves five crucial functions. It enables movement by providing attachment points for muscles through tendons and ligaments. It creates a framework and support structure, with your backbone supporting your upper body. Your bones offer protection for vital organs—your skull shields your brain while ribs protect your heart and lungs.
Surprisingly, bones produce blood cells through tissue called marrow in their centers. Finally, bones act as a storage facility for minerals like calcium and phosphorus that your body needs.
Did you know? Every bone in your body serves at least one of these five functions, and many serve multiple purposes simultaneously!
